It is conceivable that increasingly new battery systems (rechargeable battery systems) for example with lithium-ion rechargeable batteries, lithium-polymer rechargeable batteries or nickel-metal hybrid rechargeable batteries, are used increasingly both in stationary applications, for example in wind turbines, and in mobile applications, for example in electric motor vehicles (electric vehicles, EVs) or hybrid vehicles (hybrid electric vehicles, HEV), as rechargeable electrical energy stores (EES).
The battery systems need to meet very stringent requirements as regards the usable energy content, the charging/discharging efficiency, the reliability, the life and the undesirable loss of capacity owing to frequent partial discharge.
A battery system comprises a large number of battery cells. Owing to their cell internal resistance and the electrochemical processes occurring, the battery cells heat up during charging and discharging. The battery cells can be interconnected in series in order to increase the electric voltage and/or interconnected in parallel in order to increase the maximum electric current. In this case, the battery cells can be combined to form battery modules or battery units. When used for driving vehicles, for example, approximately 100 battery cells (as a traction battery) can be interconnected in series or in parallel. In a high-voltage battery system, the total voltage can therefore be 450 V or even 600 V, for example.
In order to ensure the operation and life of the battery module or battery system, it is therefore necessary to connect the electrical connections (cell terminals) of the battery cells to one another in a reliable manner. In order to connect the cell terminals, cell connectors are used, wherein the cell connectors comprise an electrically conductive material, for example a metal such as aluminum (Al) or copper (Cu) and/or are connected to the cell terminals by means of bonding, welding or screwing, for example. The cell connectors can be in the form of elastically and/or plastically deformable cell connectors in order to protect the cell terminals from excessively high forces and/or bending torques. Thus, the cell connectors can also compensate for manufacturing tolerances and/or operation-related relative movements of the battery cells.
JP H11-86831 already discloses a two-part cell connector which is designed to be displaceable along a multiplicity of cell terminals.
In order to further increase the functionality and reliability of batteries (rechargeable batteries) and battery systems (rechargeable battery systems), however, it is necessary to provide an improved cell connector.